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This paper investigates and compares two popular combined winding configurations for bearingless machines, the multi-phase (MP) and dual-purpose no-voltage (DPNV) windings. Each of these winding configurations has the ability to independently create suspension force and drive torque using the same stator coils. The paper develops analogous bearingless motor force and torque models, space vector equivalent circuits, and a current regulation architecture for each combined winding approach. A comprehensive comparison is made between the two combined winding topologies by using these analogous models and through an experimental study. It is shown that, from a motor design perspective, these combined winding topologies are equivalent for certain design conditions, but that each winding places very different demands upon the drive power electronics. The paper concludes that the optimal choice of winding configuration depends on the machine parameters and the expected loading and drive cycle. When compared in terms of total current stress exerted on the bearingless drive, the MP winding is preferred when over half of the coil current is used to produce torque rather than force. In terms of the drive's volt-ampere rating, the DPNV winding is shown to be advantageous for high operating speeds and low torque values.

The development over the last decade of the district heating (DH) network of Gleisdorf (Austria) represents an innovative example for a transition to a 4th generation DH network (4GDH). The local DH operator has strong ambitions towards implementing a highly efficient, nearly 100% renewable DH system using local resources. These goals will be achieved by the development and implementation of a novel control strategy, namely a “Virtual Heating Plant” (VHP) control concept. The VHP concept is an intelligent high level control system using operating data for real time calculations and a 24h prediction to optimise the overall DH network. The VHP control is fully implemented into the DH system and led to an improved and more flexible unit commitment, higher solar yields and more stable operating conditions. This paves the way to integrate multiple decentralised local heat sources and existing boiler units as well as other systemic approaches (e.g. sector coupling with waste water treatment plant, cascading heat supply out of the return pipe, stepwise system temperature reduction, implementation of an intelligent, decentral storage concept) and non-technical measures (e.g. user and stakeholder integration).

Background: Nowadays physical activity (PA)/exercise is an important component of cystic fibrosis (CF) therapy. The aim of the study was to assess the barriers to PA and the barrier management and to explore the effect of supervision on the barriers and barrier management during an exercise program. Methods: In total, 88 people with CF (pwCF) of the ages 6 to 50 years old (mean 24.2 ± 7.9 yrs) participated in the partially supervised 12-month exercise program and filled in a structured and validated questionnaire about barriers to sports and barrier management at baseline. Additionally, 23 pwCF filled in the questionnaire after 6 months and 12 months. The items were clustered into physical and psychosocial barriers and into preventive counter strategies and situational counter strategies and analyzed at baseline and over time. Results: Physical barriers were more relevant than psychosocial barriers and no trend could be seen in the situational and preventive counter strategies. When divided in subgroups, the less active pwCF (7500 steps/day), physical barriers, and psychosocial barriers showed no significant differences. However physical barriers showed a tendency to have a higher value in the less active group compared to the more active group (p > 0.05). Stratified by age or FEV1%pred between the subgroups, no differences could be seen regarding barriers and counter strategies. Conclusions: Physical barriers seemed to have a higher priority when it comes to not participating in PA/exercise. Supervision over 6 months during an exercise program did not show a beneficial effect on barriers and barrier management. Besides the motivational aspect of sport counselling, the volitional aspect seemed to be more important to incorporate more PA into daily life. Individual barriers and their concrete counter strategies should be discussed with the patient with CF. Sport counselling is needed permanently and should be part of the CF routine care.

Bulk heterojunction organic solar cells (BHJ‐OSCs) are designed to overcome inefficient charge generation and limited exciton diffusion of organic semiconductors. However, there are some disadvantages involving inherent voltage losses, microstructure control, and operational instability. Bilayer solar cells (BL‐OSCs) without mixed regions are free from these problems and offer a platform to explore the photophysical processes at the donor–acceptor interface. Here, a breakthrough for n‐i‐p BL‐OSCs in charge generation efficiency is reported. A gradual adjustment of the molecular interface orientation of the polymer donor (PM6) is accompanied by the evolution of charge‐transfer states and Forster energy transfer. Besides, less recombination losses and superior morphological stability of BL‐OSCs are achieved at a PCE comparable to that of BHJ‐OSCs with similar layer thickness. This investigation confirms the feasibility of manufacturing BL‐OSCs by a transfer printing method and provides a versatile architecture to study fundamental interface phenomena in OSCs independent from microstructure disorder.

Identification and investigation of strain at buried interfaces in halide perovskite photovoltaics are crucial for directing research on the performance and stability of perovskite solar cells. In this work, we find a gradual shift in the bandgap of up to 60 meV over a perovskite layer thickness of 300 nm caused by interfacial strain. This graded bandgap is desired from the aspect of device engineering. However, in parallel, the increased defect density causes charge recombination at the buried interface. These two effects compensate each other, resulting in an overall performance improvement under standard one sun illumination. Nevertheless, the disadvantage of enhanced defect density is clearly observed at low light intensities, where the device performance becomes dominated by charge recombination and ion migration. Moreover, the strained interfaces are proven to induce enhanced defect densities, causing significantly accelerated device degradation under illumination as well as in the dark.

Wahrend sich die medizinischen Umgebungsbedingungen in den letzten Jahren fur weiterzubildende Facharztinnen und Facharzte in der Orthopadie und Unfallchirurgie (O&U) stetig und teilweise drastisch veranderten, blieben Ausbildungsinhalte und -anforderungen zur Weiterbildung gleich. Weil viele Kernleistungen der O&U – wie gerade die Arthroskopie – vorwiegend ambulant in niedergelassenen Strukturen erbracht werden, gilt es, diese Strukturen an der Ausbildung zu beteiligen. Innovative Konzepte dafur waren erforderlich, scheitern aber oft an den Sektorengrenzen, an den formalen Anforderungen und nicht zuletzt an der vollig fehlenden wirtschaftlichen Abbildung der Ausbildung in der Niederlassung. Im Folgenden wird ein Modell vorgestellt, wie operative Weiterbildung trotzdem funktionieren kann.

Summary Organic solar cells (OSCs) based on non-fullerene acceptors (NFAs) have developed very fast in recent years. A proper balance among power conversion efficiency (PCE), stability, and production cost needs further elaboration. Here we investigate the industrial viability of highly efficient OSCs based on several representative NFAs. The most stable OSCs exhibit PCE of ∼8% along with extrapolated T80 lifetime (80% of the initial PCE) of over 11,000 hr under equivalent 1 sun illumination, which would lead to a very impressive operational lifetime approaching 10 years. Photo-stability is strongly dependent on the end-group and side-chain engineering of the NFAs. Breaking of conjugation during photo-aging leads to increased energetic traps. Fluorination of the end-group stabilizes molecules against light soaking, while adding methyl groups shows an opposite trend. Side-chain modification can significantly influence the morphological stability. Reducing synthetic complexity of this class of NFAs will ultimately push the organic photovoltaics technology into real-life applications.

The operational stability of organic solar cells (OSCs) is the essential barrier to commercialization. Compared to thermally-induced degradation, photo-stability of OSCs is far away from being resolved. Here, we demonstrate that the thermal- and photo-degradation of metastable bulk-heterojunction OSCs are governed by the same mechanism. Understanding the fundamental principles behind this mechanism is of significant importance to fully address the instability issues. Structural incompatibilities between the donor and acceptor molecules are identified as the main origin of the instability. Further, we introduce a top-down approach mainly based on their melting temperature and interaction parameters to rationally screen molecular phase stabilizers from a database with more than 10 000 small molecules. Eventually, five chemicals were selected to validate our concept and tested in unstable organic solar cells. 1,4-Piperazine, which possesses a high melting point, good miscibility with polymers and the capability of forming inter-molecular hydrogen bonding, can indeed stabilize the mixed amorphous phases, leading to significantly improved stability of otherwise metastable OSCs.

There is a strong market driven need for processing organic photovoltaics from eco-friendly solvents. Water-dispersed organic semiconducting nanoparticles (NPs) satisfy these premises convincingly. However, the necessity of surfactants, which are inevitable for stabilizing NPs, is a major obstacle towards realizing competitive power conversion efficiencies for water-processed devices. Here, we report on a concept for minimizing the adverse impact of surfactants on solar cell performance. A poloxamer facilitates the purification of organic semiconducting NPs through stripping excess surfactants from aqueous dispersion. The use of surfactant-stripped NPs based on poly(3-hexylthiophene) / non-fullerene acceptor leads to a device efficiency and stability comparable to the one from devices processed by halogenated solvents. A record efficiency of 7.5% is achieved for NP devices based on a low-band gap polymer system. This elegant approach opens an avenue that future organic photovoltaics processing may be indeed based on non-toxic water-based nanoparticle inks., Water-based semiconducting polymer nanoparticles are eco-friendly and non-toxic but their performance suffers from the surfactants. Here Xie et al. design an approach to minimize the amount of residual surfactant in these nanoparticles and make high-efficiency and stability solar cells.

This work deals with a compact and efficient permanent magnet excited synchronous machine to be used as paraglider towing winch. A battery supply with a voltage of only 48V is chosen for mobility and safety reasons. A rough machine design is first carried out analytically. After predesign, the final machine geometry is genetically optimized by 2D finite element method simulation using the software tool SyMSpace. After manufacture, the drive is commissioned with field-oriented control and the expected machine characteristics are compared with measurement results. Finally, also two self-sensing rotor angle estimation methods (one for the lower and one for upper speed range) are implemented and evaluated as back-up system to the installed rotor angle encoder.

The preparation of a highly ordered nanostructured transparent electrode based on a combination of nanosphere lithography and anodization is presented. The size of perfectly ordered pore domains is improved by an order of magnitude with respect to the state of the art. The concomitantly reduced density of defect pores increases the fraction of pores that are in good electrical contact with the underlying transparent conductive substrate. This improvement in structural quality translates directly and linearly into an improved performance of energy conversion devices built from such electrodes in a linear manner.

Small cooling fan failures are attributed to bearings. If a propeller rotates without any contact by magnetic levitation technology, high-speed rotation and long durability can be achieved. Thus, the authors are developing a small size maglev type motor. The Axial force/Torque Motor (AFTM) can generate axial bearing force and drive torque force in one unit. To increase the filling rate and manufacturing accuracy of winding, we used flex Printed Circuit Board (PCB) technology for AFTM. Coils are formed by winding the flex PCB around the back yoke. To higher manufacturable and improve the performance of AFTM, it is desirable to make flex PCB patterns correctly and increase the occupation ratio of copper. In this paper, we investigated the manufacturable layer configuration of special flex PCBs. Several prototypes with a different cover and copper thickness were manufactured and evaluated. We succeeded in producing a printed pattern with a copper thickness of 50 µm and a polyimide thickness of 5 µm. We could obtain a high filling factor.

Magnetic geared motors offer many advantages over mechanical gearboxes, such as reduced maintenance and intrinsic overload protection. However, in terms of durability, the limited lifetime of mechanical bearings holding the high-speed rotor is a main concern. In order to solve the problem, this paper proposes a magnetic geared motor with an additional set of three-phase winding to provide suspension magnetic force to the high-speed rotor. The basic structure and the operational principle are investigated and verified through finite element analysis.

A possible combination of a magnet gear and a high-speed bearingless motor has been investigated. The high-speed side is driven by magnetically suspended bearingless motor, which is integrated in the magnetic gear. The initial study has shown that, the eddy current loss increases at high speed due to the influence of harmonic flux. In order to improve the efficiency, several structures are proposed and compared with the sintered and bonded NdFeB permanent magnets. The proposed magnetic geared bearingless motor is formed to be compact light weighted, and high efficiency to the IE3 isdustrial motor with an output of 550W and 3,000rpm.

A very simple and therefore wide-spread way to control motor speed and torque is to regulate the stator voltage by pulse width modulation (PWM). Depending on the modulation type, number of inverter levels and modulation index of the PWM, various spectral components occur in the supply signal and inject ripple current in the motor phases. This current distortion can cause significant additional losses in the stator and rotor core, permanent magnets and windings of an electric machine. Therefore, it is important to consider these losses in an early design stage. In this work an efficient calculation method for harmonics of multilevel PWM signals and generated phase currents with di□erent modulation types is presented. The PWM losses are calculated via 2D finite element method (FEM) analyses. The calculation and simulation workflow is realized within the software tool SyMSpace and applied to a three-phase permanent magnetic synchronous machine (PMSM).

The turnover of the epidermis beginning with the progenitor cells in the basal layer to the fully differentiated corneocytes is tightly regulated by calcium. Calcium more than anything else promotes the differentiation of keratinocytes which implies the need for a calcium gradient with low concentrations in the stratum basale and high concentrations in the stratum granulosum. One of the hallmarks of skin aging is a collapse of this gradient that has a direct impact on the epidermal fitness. The rise of calcium in the stratum basale reduces cell proliferation, whereas the drop of calcium in the stratum granulosum leads to a changed composition of the cornified envelope. We showed that keratinocytes respond to the calcium induced block of cell division by a large increase of the expression of several miRNAs (hsa-mir542-5p, hsa-mir125a, hsa-mir135a-5p, hsa-mir196a-5p, hsa-mir491-5p and hsa-mir552-5p). The pitfall of this rescue mechanism is a dramatic change in gene expression which causes a further impairment of the epidermal barrier. This effect is attenuated by a pseudogene (SPRR2C) that gives rise to a lncRNA. SPRR2C specifically resides in the stratum granulosum/corneum thus acting as a sponge for miRNAs.

Pharmacological targeting of Hedgehog (HH)/GLI has proven effective for certain blood, brain and skin cancers including basal cell carcinoma (BCC). However, limited response rates and the development of drug resistance call for improved anti-HH therapies that take into account synergistic crosstalk mechanisms and immune evasion strategies.In previous work, we demonstrated that crosstalk of HH/GLI with pro-inflammatory Interleukin-6 (IL6) signaling drives BCC by promoting tumor cell proliferation [1]. In the present study, we screened for possible mechanisms of cancer immune evasion regulated by synergistic HH-IL6 signaling and identified the immunosuppressive enzyme indoleamine 2,3-dioxygenase 1 (IDO1) as a novel transcriptional target co-regulated by HH-IL6 signaling. Analysis of thecis-regulatory region of IDO1 by chromatin-immunoprecipitation revealed co-occupancy of this region by HH- IL6 induced GLI1 and STAT3 transcription factors along with active chromatin marks at the histone level. Elevated expression of IDO1 in human BCC with high-level HH and IL6 signatures supports the clinical relevance of our mechanistic data. Genetic inhibition of GLI1 expression prevented the induction of IDO1 expression in response to IL6/STAT3 and IFNγ/STAT1 signaling in human melanoma cells. Pharmacological targeting of HH signaling at the level of GLI proteins interfered with IDO1 expression and consequently prevented the production of the immunosuppressive metabolite kynurenine generated by active IDO1 from tryptophan. Further, inhibition of GLI1 enhanced the efficacy of the selective IDO1 inhibitor epacadostat. Of note, inhibition of HH/GLI signaling in melanoma cells not only reduced IDO1 expression but also interfered with the repression of T cell activation by attenuating IDO1/kynurenine-mediated immunosuppression. These data identify the immunosuppressive IDO1-kynurenine pathway as a novel pro-tumorigenic effector of oncogenic HH-IL6 and GLI-STAT cooperation. Our data suggest simultaneous pharmacological targeting of the HH/GLI, JAK/STAT and IDO1- kynurenine axis as rational combination therapy in skin cancers.

Great attention has been paid to developing low bandgap non-fullerene acceptors (NFAs) for matching wide bandgap donor polymers to increase the photocurrent and therefore the power conversion efficiencies (PCEs) of NFA organic solar cells, while pyrene-core based acceptor–donor–acceptor (A–D–A) NFAs have been mainly reported via the 2,9-position connection due to their bisthieno[30,20-b']thienyl[a,h]pyrene fused via a five-membered ring bridge at the ortho-position of pyrene as the representative one named FPIC5, which has prohibited further narrowing their energy gap. Herein, an acceptor FPIC6 was exploited by creating the 1,8-position connection through fusing as bisthieno[30,20-b0]thienyl[f-g,m-n]pyrene linked at the bay-position via a six-membered bridge, with enhanced push–pull characteristics within such A–D–A structure. As a structural isomer of FPIC5, FPIC6 exhibited a much lower bandgap of 1.42 eV (1.63 eV for FPIC5). Therefore, the photocurrent and PCE of PTB7-Th:FPIC6 cells were improved to 21.50 mA cm2 and 11.55%, respectively, due to the balanced mobilities, better photoluminescence quenching efficiency and optimized morphology, which are both40% better than those of PTB7-Th:FPIC5 cells. Our results clearly proved that a pyrene fused core with 1,8-position connection with electron-withdrawing end groups instead of 2,9-position connection is an efficient molecular design strategy to narrow the optical bandgap and improve the photovoltaic performance of NFA based OSCs.

GHG and CO2 legislations in US, Europe and China demand a reduction of emissions in the range of 25 to 30% for heavy commercial vehicles in the current decade. To meet these challenging targets, a further increase of the efficiency of the internal combustion engine is one of various optimization parameters. AVL develops engine concepts to increase the brake thermal efficiency (BTE) to 50%, focusing on base-engine improvements. This requires a spec. fuel consumption below 170 g/kwh. This article shows AVL’s research results, which are based on the testing results of a single cylinder research engine and on 1D-thermodynamic simulations. From these results, challenges for design and friction requirements are derived. Finally, the strengths and weaknesses of diesel engine concepts with the potential for 50% BTE are discussed.

Persistent activation of hedgehog (HH)/GLI signaling accounts for the development of basal cell carcinoma (BCC), a very frequent nonmelanoma skin cancer with rising incidence. Targeting HH/GLI signaling by approved pathway inhibitors can provide significant therapeutic benefit to BCC patients. However, limited response rates, development of drug resistance, and severe side effects of HH pathway inhibitors call for improved treatment strategies such as rational combination therapies simultaneously inhibiting HH/GLI and cooperative signals promoting the oncogenic activity of HH/GLI. In this study, we identified the interleukin-6 (IL6) pathway as a novel synergistic signal promoting oncogenic HH/GLI via STAT3 activation. Mechanistically, we provide evidence that signal integration of IL6 and HH/GLI occurs at the level of cis-regulatory sequences by co-binding of GLI and STAT3 to common HH-IL6 target gene promoters. Genetic inactivation of Il6 signaling in a mouse model of BCC significantly reduced in vivo tumor growth by interfering with HH/GLI-driven BCC proliferation. Our genetic and pharmacologic data suggest that combinatorial HH-IL6 pathway blockade is a promising approach to efficiently arrest cancer growth in BCC patients.

This paper studies the modeling and field-oriented control (FOC) for hysteresis motors, with the goal of achieving position control of hysteresis motors for servo applications. Hysteresis motors include a wide range of machines with solid cylindrical or ring-shaped steel rotors, which generate torque primarily via the magnetic hysteresis effect of the rotor material. Previously, hysteresis motors have been mainly used under open-loop operation. However, they are also attractive for position control in some special applications such as in-vacuum operation or when smooth running and high speed is required. In this paper, an equivalent circuit model for hysteresis motors that describes the motor's transient-time dynamics is introduced, and a state-space model for hysteresis motors is developed. This model is used to construct a rotor flux orientation observer for the FOC for hysteresis motors. Three methods for estimating the rotor field angle are introduced. The proposed FOC-based position control method was tested with three hysteresis motors, including two custom-made motors of different rotor materials and one off-the-shelf hysteresis motor. Experimental results show that position control for all three hysteresis motors can reach a bandwidth of 130 Hz with the proposed methods. To the authors’ best knowledge, this is the first experimental study on FOC and position control for hysteresis motors.

Magnetlager sind aus etlichen industriellen Anwendungen nicht mehr wegzudenken, in anderen erscheint ein Einsatz in Zukunft vielversprechend. Durch die Magnetlagertechnik werden Effizienzsteigerungen unterschiedlicher Art ermoglicht – sowohl auf direkte Weise durch Verringerung der Lagerverluste im Vergleich zu mechanischen Lagerungen, als auch durch Verbesserungen im industriellen Prozess, die erst durch die besonderen Eigenschaften der Magnetlagerung erzielt werden konnen. Im ersten Teil dieses Beitrags werden die unterschiedlichen zur Verfugung stehenden Topologien der Magnetlagertechnik vorgestellt. Der zweite Teil stellt effizienzsteigernde Masnahmen in der Magnetlagertechnik anhand eines lagerlosen Hochgeschwindigkeitsmotors vor. Im abschliesenden, dritten Teil, werden Moglichkeiten zur Effizienzsteigerung durch die Magnetlagertechnik prasentiert. Dies geschieht anhand von vier Anwendungsgebieten, in denen Magnetlager bereits wesentlich zur Performance des Gesamtsystems beitragen, gewisse Prozessschritte erst ermoglichen oder dies in Zukunft tun konnten.